Compounded hydrocarbon oil



Patented Jan. 19, 1943 UNITED STATES PATENT OFFICE 2,308,503 COMPOUNDED HYDROCARBON 011.

Bruce B. Farrington, James 0. Clayton, and Dorr H. Etzler, Berkeley, Calii'., assignors to Standand Oil Company of California, San Francisco, Calif., a corporation of Delaware No Drawing. Application August 2, 1940, Serial No. 350,055

15 Claims.

This invention relates to new and useful compositionsof matter and involves a composition comprising a hydrocarbon oil such as a mineral oil containing a polyvalent metal salt of certain obtain desired characteristics involves empirical phenomena. The present invention provides a compounded-lubricating oil having one or more properties improved by the incorporation of certain metal salts. A brief discussion 'of significant properties of lubricating oils may serve to clarify the problems of the lubricating art.

It has long been the desire of the lubricating oil compounding art to obtain an oil, particularly of petroleum origin, which alone or with the addition of relatively small amounts of compounding agents would resist deterioration or degradation when subjected for long periods of time to high temperatures and pressures in the presence of metals, air or oxygen or hydrocarbon partial combustion products. Deterioration of the character referred to manifests itself in diverse effects, depending upon the nature and degree of refinement of the hydrocarbon oil and upon the "environment to which it is subjected. In Diesel gases at pressures as high as 750 to 1150 lbs. persquare inch causes the deposition of oil degradation products of such a cementitious character as-to effectively take piston rings out of service.

In automobile engines the deposition of sludge in p the crankcase oils and the formation of varnish on the cylinder walls of the engine are observed to be the result of oxidation and/or polymerization phenomena occurring in the degradation process. The corrosion of hard metal bearing sur- 7 faces of the type represented by cadmium-silver and copper-lead alloys also is a diificulty encountered from the deterioration of lubricating oils in internal combustion engines or other serv- I of Mendeleefis Periodic Table of the Elements ices. The adverse effect of deterioration of hydrocarbon oils at elevated temperatures is aggravated by the fact that improvements in the mechanical arts have broughtabout increasing severity in the conditions to which the oils-are subjected.

It has also been the practice in the lubricating oil art to improve other properties of lubricants by adding ingredients to mineral oil fractions for enhancing the oiliness characteristics, the wear reducing action, the film strength, the color stability, and the viscosity index of lubricating oils.

It is an object of the present invention to improve one or more of the above-discussed prop-'- erties of lubricatingoils (i. e., stability against piston ring sticking, varnish formation, sludging, corrosivity to metal bearing surfaces, oiliness, wear reduction, film strength, color stability, or viscosity index) by incorporating in hydrocarbon oils 'a polyvalent metal salt of certain types of organic acids.

The lubricating oilsof this invention are characterized by the presence therein of a polyvalent metal alkyl carboxylate having a substituent with at least One atom of an element of Group VI-B near a carbonyl group of the carboxylate. The

substituent is preferably no more than about three carbon atoms removed from a carbonyl group of the metal carboxylate and at least one atom of group VI-B in said substituent should preferably be directly connected to a carbon atom near a carbonyl group of the compound. By

polyvalent metal alkyl carboxylate it is intendit is intended to designate compounds having at least one of the above-described substituents in at least one of the positions, alpha, beta or gamma, with respect to a carboxyl group of the compound and preferably with respect to one of the metal salt-forming carboxyl groups in the compounding agent. It is preferred that the substituent be such that a sulfur, selenium or tellurium atom is directly connected to a carbon atom in the aforesaid alpha, beta or gamma posi- Gamma thioketo substituted tion. Exemplary compounding agents of this invention are polyvalent metal salts of acids char- J; J; acterized by the presence 'therein of chemical- I l 1 groups such as the following: 5

1. Thi oalkyl substituted metal carbowlates Alpha beta dltmoketo substituted Alpha thioalkyl substituted I a r fi Alpha gamma dithioketo substituted Beta. thioallwl substituted 1 B-C- O-Y n-i -x-t i-tii-y I Gm substituted 1 '15 Beta gamma dithioketo substituted R-{i-X-Jf--Jf-Y I R0-c- :J -Y

. In the above formulae "x" be -s-. fr i Alpha beta gamma. trithioketo substituted may be alkyl or hydrogen; and Y may be n-c=-o-o-Y :-o-, -s-, :-o-,' or -r :-s- I 0 s A In the above formulae R and "Y" have the 2. Mercapto or mercapttde substituted metal same significance as set forth above; and "x:

carbozulates may be -'-8, Se or -'I'e.

A ph Substituted 4. Thtoester substituted metal carborillates u-t-Y Alpha thioester substituted i1 1 3,- Alpha betadlsubstituted. Y

I;Ba B-(J-(B-Y Betathioester substituted Beta substituted k v at at R- -Y a l -xlBa Bi 40 Alpha beta gamma trisubstituted Gamma thioester substituted imt 131 131 *IBI 4,, (:J--Y Gamma substituted i-xm:

In I I In the 8b0Vr:vf10r111:11;1aet1R; tandlzlhave the t aignifleaneep 0 se 0 analkyi Beta gamma dlsubstimted group; and "x3" and xc' may be either oxygen orsuliursolongasatleastoneissulrunthatis, R- -Y the thioester ma? be either a thiol ester, a thion i J ester or a dithioester group. Alpha gamma disubstituted 5.; Sulfinyl substituted metal carbon latex" & & 5 Y Alpha sulflnyl substituted iBi I 1111 RFC-Y In the above formulae R. and Y" have the 0 a same significance as indicated above; "Xi" may be may be alkyl, Beta sulfinyl substituted metal or hydrogen; and at least one R1 is a metal or hydrogen. H

n-c-d-Y 3. Thiono substituted metal carboa'zllates Alpha thioketo substituted R'CY - Gamma sulflnyl substituted I Beta thioketo substituted 1g 1g n-oy a-o-l i-v 7. Metal carbomylate with sulfate ester substituent Sulfate ester in gamma position 8. Metal carboxylate with sulfite ester substituent Sulfite esterin alpha position Sulfite ester iri beta position R-(J-(IJ-Y o=s-o R1 Sulfite ester in gamma position 9. Sulfino substituted metal carbomylates Alpha sulfino substituted R-(i-Y R:-%=O

Beta sulfino substituted Gamma sulfino substituted l Iii-i=0 10. Sulfa-substituted metal carboxylates Alpha sulfa-substituted Beta sulfo-substituted V 11. Seleninyl substituted metal carboxylates Alpha seleninyl substituted R(:)Y Se=O Beta, seleninyl substituted l2. Seleuon'yl substituted metal carbowylates Alpha selenonyl substituted R(H3Y O=Se=0 Beta selenonyl substituted Gamma selenonyl substituted 13. selenino substituted metal carbomylates Alpha selenino substituted I R(lJY RzO-Sfle 0 Beta selenino substituted I R-C-C-Y g I Rio-"e Gamma selenino substituted R-i-Ji-{J-Y R10? 14. Selenono substituted metal curboxylates Alpha selenono substituted R10 Ic= Beta selenono substituted Gamma selenono substituted RAB-ti y In each of the above series of formulae B may be alkyl or hydrogen; Y has the same significance as set forth above; R2 is an allwl radical;

and the remaining letters. are standard symbols for the chemical elements. The various unsatisfled valencesshown on the carbon atoms in the formulae may be attached to hydrogen, a carbon atom, or to an acyclicprganic radical. The unsatisfied acidic valence of the "Y group may be attached to a polyvalent metal.

The compounding ents of this invention inasoasos the sulfur type atom more than about three carbon atoms removed from the carbonyl group.

In explanation of the terminology hereinafter utilized, it is pointed out that the prefix "thio" is used to designate the substitution of sulfur for oxygen in a compound and not the substitution of sulfur for hydrogen. Thus CHaCOSH or CHaCSOH is designated thioacetic acid, whereas 'CHaSH COOH would not be called thioacetic acid but rather thioglycolic or mercapto-acetic acid. The prefixes (methy1thio)-, (amylthio) etc... written asone unhyphenated word and enclosed in parentheses refer to the groups CHaS- or CsHuS- replacing hydrogen in a molecule. For example, C5H11S-CH2COOH is written (amylthio) -acetic acid.

Examples of substituted carboxylic acids from which the oil-improving agents of this invention may be formed are:

Thioalkyl substituted whim-alpha, beta and gamma (alkylthio) substituted butyric, valeric, caproic, caprylic, capric, lauric, myristic, palmitic, and stearic acids.

Mercapto substituted acids.''alpha' or beta mercapto-propionic acid; alpha, beta or gamma mercap'to-butyric acid; alpha, beta or gamma mercapto-valeric acid; alpha, beta or gamma mercapto-caproic acid; alpha, beta or gamma mercapto-caprylic acid; alpha, beta or gamma volve two general types of sub'stltuents in metal carboxylates: ta) a homoatomic sulfur-, selenium-, or tellurium-containing substituent; and (b) a heteroatomic sulfur-, selenium-, or tellurium-contalning substituent. By homoatomic" is meant a substituent containing only one kind of atom in addition to carbon and hydrogen which may be present therein, that is, the substituent contains for example only sulfur in addition to carbon and hydrogen. Homoatomic substituents are represented by groups 1 and 3 of the foregoing type formulae, as well as group 2 when R1 is alkyl or hydrogen, and group 4 when X: and X4 both are sulfur. Hetero'atomic substituent" same is subjected to high temperatures and/or pressures in the presence of oxygen and metals.

This appears tobe true when the sulfur type I atom is attached to the delta or even epsilon carbon atom, as well as when it is attached to an alpha, beta or gamma carbon. However, improvements in the properties of lubricating oil are obtained when the sulfur type atom is attached to an alpha, beta or game. carbon (with respect to the carbonyl group of the compound) which are not obtainable in compounds having mercapto-capric acid: alpha, beta or gamma mercapt'o-lauric acidpalpha, beta or gamma mercapto-myris'tic acid; alpha, beta or gamma mercapto-palmitic acid; alpha, beta or gamma mercapto-stearic acid.

Thiono substituted acids.alpha or beta thioketo-propionic acid; alpha, beta or gamma thioketo-butyric acid;-' alpha, beta or gamma thioketo-valeric acid; alpha, beta or gamma thicketo-caprolc acid; alpha, beta or gamma thioketo-caprylic acid, alpha, beta or gamma thioketo-capric acid; alpha,'beta or gamma thioketo- -lauric acid; alpha, beta or gamma thioketo-myristic acid; alpha, beta or gamma thioketo-palmitic acid; alpha, beta or gamma thioketo-stearic acid.

Acids having a thioeste'r substituent.-acetic. propionic, butyric, valeric, caproic, caprylic, capric, lauric, myristic, palmitic and stearic acids having a thiol ester, a thiono ester, or a dithio ester substituent, any one of which may be in any one of the positions-alpha, beta or gamma with respect to the carboxyl group of said acids.

Sulfinyl substituted acids-alpha or beta sulfinyl-propionic acid; alpha, beta or gamma sulfinyl-butyric acid; alpha, beta or gamma suliinylvaleric acid; alpha, beta or gamma sulfinyl-caproic acid; alpha, beta or gamma sulfinyl-caprylic acid; alpha, beta or gamma sulflnyl-capric acid; alpha, beta or gamma sulflnyl-lauric acid; alpha,

beta or gamma sulfinyl-myristic acid; alpha, beta or gamma sulfinyl-palmitic acid; alpha, beta or gamma sulfinyl-stearic acid.

. Sulfonyl substituted acids-alpha or beta sulfonyl-propionic acid; alpha, beta or gamma sulfonyl-butyric acid; alpha, beta or gamma sulfonyl-valeric acid; alpha, beta or gamma sulfonyl-caproic acid; alpha, beta or gamma sulfonyl-caprylic acid; alpha, beta or gamma sulfonyl-capric acid; alpha, beta or gamma sulfonyllauric acid; alpha, beta or gamma sulfonyl-msrristic acid; alpha, beta or gamma sulfonyl-palmitic acid; alpha, beta or gamma sulfonyl-stearic acid.

Acids containing an organic sulfate ester sub- 'sulfo-propionic acid;

- seleninyl-caproic acid; alpha, beta or stituent.- -acetic, propionic, butyric, valeric, caproic, caprylic, capric, lauric, myristic, palmitic, and stearic acids having an organic sulfate ester group in either the alpha, beta or gamma position with respect to the carboxyl group of said acids.

Acids containing an organic sulfite ester substituent.acetic, propionic, butyric, valeric, caproic, caprylic, capric, lauric, myristic, palmitic, and stearic acids having an organic sulfite ester group in either the alpha, beta or gamma position with respect to the carboxyl group of said acids.

Sulfino substituted acids.alpha or beta alkyl sulfino-propionic acid; alpha, beta or gamma alkyl sulfino-butyric acid; alpha, beta .or gamma alky1 sulfino-valeric acid; alpha, beta or gamma alkyl sulfino-caproic acid; alpha, beta or gamma alkyl sulfino-caprylic acid, alpha, beta or gamma alkyl sulfino-capric acid; alpha, beta or gamma alkyl sulfino-lauric acid; alpha, beta or gamma alkyl sulfino-myristic acid; alpha, beta or gamma alkyl sulfino-palmitic acid; alpha, beta or gamma alkyl sulfino-stearic acid. O

Sulfa-substituted acids.alpha or' beta alkyl alpha, beta or gamma alkyl sulfo-butyric acid; alpha, beta or gamma alkyl sulfo-valeric acid; alpha, beta or gamma alkyl sulfo-caproic acid; alpha, beta or gamma alkyl sulfo-caprylic acid; alpha, beta or gamma alkyl sulfo-capric acid; alpha, beta or gamma alkyl sulfo-lauric acid; alpha, beta or gamma alkyl sulfo-myristic acid; alpha, beta or gamma alkyl sulfo-palmitic acid; alpha, beta or gamma alkyl sulfo-stearic acid.

Seleninyl substituted acids.--alpha or beta seleninyl-propionic acid; alpha; beta or gamma seleninyl-butyric acid; alpha, beta or gamma seleninyl-valeric acid;- alpha, beta or gamma gamma gamma gamma gamma gamma selenino-propionic acid; alpha, beta or gamma alkyl selenino-butyric acid; alpha, beta or gamma alkyl selenino-valeric acid; alpha, beta or gamma alkyl seienino-caproic acid; alpha, beta or gamma alkyl selenino-capryli'c acid; alpha, beta or gamma alkyl selenino-capric acid; alpha, beta or gamma alkyl selenino-lauric acid; alpha, beta or gamma alkyl selenino-myristic acid; alpha, beta or gamma alkyl selenino-palmitic acid; alpha, beta or gamma alkyl selenino-stearic acid.

Selenono substituted acids.-alpha or beta alkyl selenono-propionic acid; alpha, beta or gamma alkyl selenono-butyric acid; alpha, beta or gamma alkyl selenono-valericacid; alpha, beta or gamma alkyl selenono-caproic acid; alpha.

beta or gamma alkyl selenono-caprylic acid;

gamma gamma alpha, beta or gamma alkyl selenono-capric acid; alpha, beta or gamma alkyl selenono-lauric acid; alpha, beta or gamma alkyl selenono-myristic acid; alpha, beta or gamma alkyl selenono-palmitic acid; alpha, beta or gamma alkyl selenonostearic acid.

' Polycarboxylic acids containing thioalkyl, mercapto, mercaptide, thiono, thioester, sulfinyL. sulfonyl, sulfate ester, sulfite ester, sulfino, sulfo,

seleninyl, selenonyl, selenino or selenono substituents in an alpha, beta or gamma position with respect to a carboxyl group of-the acid likewise may be utilized. For example, thiotartronic acid and its alkyl homologues, thiomalic acid and its homologues, thiotartaric acid, thiocitric acid and the like represent suitable acids for the preparation of the compounding agents of this invention.

The metals whose substituted carboxylates are useful for the purposes of this invention preferably have valences from two to four inclusive,

and the salts of calcium, barium, magnesium,

aluminum, chromium, cobalt, lead, manganese, tin and zinc are of particular utility. It is to be understood that the carboxylates or salts of each and every one of these metals formed by metal replacing the hydrogen of a carboxyl group in each and every one of the substituted acids hereinbefore listed are a part of the invention. In other words, to save space, the calcium salt or carboxylate of each of the substituted acids here inbefore recited, the barium salt or carboxylate of each of the acids, the magnesium salt, or carboxylate of each of the acids, the aluminum salt or carboxylate of each of the acids, the chromium salt or carboxylate of each of the acids, the cobalt salt or carboxylate of each of the acids, the lead salt or carboxylate of -each of the acids, the manganese salt or carboxylate of each of the acids, the tin salt or carboxylate of each of the substituted acids hereinbefore recited, and the zinc salt or carboxylate of each of the acids are not actually listed herein but the invention in its broad aspects contemplates each and every one of such salts as a compounding agent for lubricating oils. According y. it is to be understood that the present specification is to be considered as if each of the foregoing metal salts of each of the previously listed acids was specifically recited herein. Although the alkali metals, sodium and potassium, are not precluded from the broadest aspects of the invention the carboxylates of these latter metals tend to cause the compounded oil to form emulsions with water, and where the lubricating service to be encountered is the lubrication of internal combustion engines such a tendency is undesirable.

Examples of type 1 compounds.-Speciflc examples of compounded oils containing thioalkyl substituted carboxylates are:

' s. a E; 30lubricating'oi1:

In each case the oil is preferably an acid refined Western (naphthenic base) oil.

Examples of type 2 compounds-Specific examples of compounded oils containing mercapto substituted carboxylates are:

S. A. E. 30 lubricating oil:

+1% calcium alpha. mercapto-stearate +1%v magnesium alpha mercapto-stearate +1% aluminum alpha mercapto-stearate +1% chromium alpha mercapto-stearate +1% calcium alpha mercapto-palmltate +1% magnesium alpha'mercapto-palmitate +1% aluminum alpha mercapto-palmitate +1% chromium alpha mercapto-palmitate +1% calcium alpha mercapto-myristate +1% magnesium alpha mercapto-myristate +1% aluminum alpha mercapto-myristate +1% chromium alpha mercapto-myristate In each case the oil is preferably an acid refined Western (naphthenic base) oil.

Emples of type 3 compounds.-Speciflc ex-. amples oi. compounded oils containing thioketo substituted carboxylates are:

S. A. E. 30 lubricating oil:

+1% calcium alpha thioketo stearate +1% magnesium alpha thioketo stearate +1% aluminum alpha thioketo stearate +1% chromium alpha thioketo stearate +1% calcium alpha thioketo palmitate +1% magnesium alpha thioketo palmitate +1% aluminum alpha thioketc palmitate +1% chromium alpha thioketo palmitate +1% calcium alpha thioketo myristate +1% magnesium alpha thioketo myristate +1% aluminum alpha thioketo myristate +1% chromium alpha thioketo myristate In each case the oil is preferably an acid refined .Western (naphthenic base) oiL Examples of type 4 cmpounds.Speciflc examples of compounded oils containing 'thioester substituted carboxylates are:

S. A. E. 30 lubricating oil:

+1% calcium cetyl thiocitrate +1% magnesium cetyl thiocitrate +1% aluminum cetyl thiocitrate +1% chromium cetyl thiocitrate +1% calcium cetyl thiotartrate +1% magnesium cetyl thiotartrate +1% aluminum cetyl thiotartrate +1% chromium cetyl thiotartrate In eachcase the oilis preferably an acid refined Western (naphthenic base) oil. 1

Examples of type 5 compounda-Speciific examples of compounded oils containing sulflnyl substituted carboxylates are:

S. A. E. 30 lubricating oil: +1% calcium alpha sulfinyl stearate +1% magnesium alpha sulfinyl stearate +1% aluminum alpha sulfinyl stearate +1% chromium alpha sulfinyl stearate +1% calcium alpha sulfinyl palmitate +1% magnesium alpha sulflnyl palmitate +1% aluminum alpha sulflnyl palmitate +1 chromium alpha sulfinyl palmitate +1% calcium alpha sulflnyl' myristate +1% magnesium alpha sulfinyl myristate aluminum alpha sulfinyl myristate +1% chromium alpha sulflnyl myristate In each case the oilis preferably an acid refined Western (naphthenic base) oil.

Examples of type 6 compounds.-Speciflc examples of compounded oils containing sulionyl substituted carboxylates are:

S. A. E. 30 lubricating 011:

+1% calcium alpha sulfonyl stearate +1% magnesium alpha sulfonyl stearate +1% aluminum alpha sulfonyl stearate +1% chromium alpha sulfonyl stearate +1% calcium alpha sulfonyl palmitate +1% magnesium alpha sulfonyl palmitate +1% aluminum alpha sulfonyl palmitate +1% chromium alpha sulfonyl palmitate +1% calcium alpha sulfonyl myristate +1% magnesium alpha sulfonyl myristate +1% aluminum alpha sulfonyl myristate +1% chromium alpha sulfonyl myristate in each case the oil is preferably an acid refined Western (naphthenic base) oil.

' Examples of type 7 c0mp0unds.Specific examples of compounded oils containing carboxylates with sulfate ester substitutent are:

S. A. E. 30"lubricating oil:

In each case the oil is preferably an acid refined Western (naphthenic base) oil.

Examples of type 8 compounds.-Speciflc examples of compounded oils containing carboxylates with sulfite ester substituent are:

S. A.- E. 30 lubricating oil:

+1%. calcium alpha ethylsuifito stearate +1% magnesium alpha ethylsulfito stearate +1% aluminum alpha ethylsulfito stearate +1% calcium alpha ethylsulflto palmitate magnesium alpha ethylsulfito palmitate i aluminum alpha ethylsulflto palmitate chromium alpha ethylfulflto palmitate calcium alpha ethylsulfito myristate tate +1% aluminum alpha ethylsulflto myristate +1% chromium alpha ethylsulfito myristate Ineach case the oil is preferably an acid refined Western (naphthenic base) oil.

chromium alpha ethylsulfito stearate magnesium alpha ethylsulflto myrisl Examples of type 9 cmpounds.-Specific. ex- In each case the oil is preferably anacid refined amples of compounded oils containing sulfino substituted carboxylates are:

myristate aluminum alpha ethylsulfino myristate +1% chromium alpha ethylsulfino myristate In each case the oil is preferably an acid refined Western (naphthenic base) oil.

Examples of type compouads.--Specific examples of compounded oils containing sulfasubstituted carboxylates are:

S. A. E. lubricating oil;

+1% calcium alpha ethylsulfo stea'rate +1% magnesium alpha ethylsulfo stearate +1% aluminum alpha ethylsulfo stearate +1% chromium alpha ethylsulfo stearate +1% calcium alpha ethylsulfo palmitate +1% magnesium alpha ethylsulfo palmitate +1% aluminum alpha ethylsulfo palmitate +1% chromium alpha ethylsulfo palmitate +1% calcium alpha ethylsulfo myristate +1 aluminum alpha ethylsulfo myristate +1% chromium alpha ethylsulfo myristate In each case the oil is preferably an acid refined Western (naphthenic base) oil.

Examples of type 11 compounds. specific ex-' amplesluf compounded oils containing'seleninyl substituted carboxylates are:

s. A. E. 30 lubricating oil:

+1% calcium alpha seleninyl stearate +1% magnesium alpha seleninyl stearate +1% aluminum alpha seleninyl stearate +1% chromium alpha seleninyl stearate +1% calcium alpha seleninyl palmitate +1% magnesium alpha seleninyl palmitate +1% aluminum alpha seleninyl palmitate +1% chromium alpha seleninyl palmitate +1% calcium alpha seleninyl myristate +1% magnesium alpha seleninyl myristate +1% aluminum alpha seleninyl myristate +1% chromium alpha seleninyl myristate- In each case the oil is preferably an acid refined Western (naphthenic base) oil,

Examples of type 12 compounda-Specific examples of compounded oils containing selenonyl substituted carboxylates are:

S. A. E. 30 lubricating oil: +1% calcium alph selenonyl stearate I +1% magnesium lpha selenonyl stearate +1% aluminum alpha selenonyl stearate +1% chromium alpha selenonyl stearate +1% calcium alpha selenonyl palmitate +1% magnesium alpha selenonyl palmitate +1% aluminum alpharselenonyl palmitate +1% chromium; alpha selenonyl palmitate +1% calcium alpha selenonyl myristate +1% aluminum alpha selenonyl myristate chromium alpha selenonyl myristate magnesium alpha ethylsulfo myristate Western (naphthenic base) oil.

Examples of type 13 comp0unds.Spe'cific-examples of compounded oils containing selenino rate aluminum alpha ethylselenino stearate chromium alpha ethylselenino stearate calcium alpha ethylselenino palmitate magnesium alpha ethylselenino palmitate aluminum alpha etlwlselenino palmitate chromium alpha ethylselenino palmitate calcium alpha ethylselenino myristate magnesium alpha ethylselenino myristate aluminum alpha ethylselenino myristate p chromium alpha ethylselenino myristate I In each case the oil is preferably an acid refined The invention likewise does not preclude carmagnesium alpha selenonyl myristate Western (naphthenic base) oil.

Examples of type 14 compounds. specific examples of compounded oils containing selenono substituted carboxylates are:

S. A. E. 30 lubricating oil:

+1% calcium alpha ethylselenono stearate +1% magnesium alpha ethylselenono stearate +1% aluminum alpha ethylselenono stearate v chromium alpha ethylselenono steamagnesium alpha ethylselenono palmitate tate chromium alpha ethylselenono palmitate calcium alpha ethylselenono myristate magnesium alpha ethylselenono myristate tate chromium alpha ethylselenono myristate In each case the oil is preferably an acid refined Western (naphthenic base) oil.

It should be understood that basic as well as neutral carboxylates may. be utilized. By basic carboxylates is meant compounds in which the carboxylic acid groups are present in an amount lnsufflcient to wholly satisfy the normal valence of the metal, thereby leaving an unsatisfied metal valence which may be attached to an hydroxyl group. By a neutral salt is meant compounds in which the carboxylic acid groups and the metal are present in stoichiometrical proportions so that the normal valence of each is fully satisfied.

boxylates'containing unsaturated carbon-to-carbon bonds, but compounds which do not polymerize are preferred.

This invention also embraces lubricating oils containing, in combination with the metal car-' boxylates having substituents as hereinbefore magnesium alpha ethylselenino stea-- aluminum alpha ethylselenono palmialuminum alpha ethylselenono myrisdisclosed, one or more of the following types of compounds:

1. Carboxylate esters having an'alkyl hydroxy substituent near a carbonyl group'of the com- P und;

2. Metal salts of organic acids, such as (a) Polyvalent metal salts of higher fatty or aliphatic acids;

(b) Metal salts of naphthenic acids: J

(c) Metal salts of oil-soluble substituted phenols;

(d) Metal salts of carboxylic acids containing an aryl substituent;

(a) Polyhydroxy phenols, condensed ring phenols, alkyl substituted phenols,.

3. Corrosion inhibitors and anti-oin'dants, such butyric, valerlc, caproic, enanthic, caprylic, capric, lauric, myristic, palmitic, stearic, and erachidic acids, as well as the corresponding esters of tartronic, tartaric and citric acids.

Among the metal salts of organic acids which may be utilized in combination with each and every one of the foregoing metal carboxylates having a substituent with at least one atom of an element of Group VI--B of Mendeleefi's Periodic Table of the Elements near a carbonyl group of the carboxylate are: aluminum laurate, aluminum oleate, aluminum stearate, aluminum ricinoleate; zinc laurate, zinc oleate, zinc stearate, zinc ricinoleate; tin laurate, tin oleate, tin stearate, tin ricinoleate; magnesium laurate, magnesium oleate, magnesium stearate, magnesium'ricinoleatetcalcium laurate, calcium oleate, calcium stearate, calcium ricinoleate; chromium laurate, chromium oleate, chromiumstearate, chromium ricinoleate; aluminum naphthenate, zinc naphthenate, magnesium naphthenate, cobalt naphthenate; cadmium naphthenate, tin

naphthenate, manganese naphthenate; aluminum, zinc, tin, magnesium, calcium and chromium salts of substituted phenols of the type formula:

in which u, v, w, a: and y are selected from the group consisting of hydrogen, alkyl, aryl, alkaryl aralkyl and cyclic non-benzenoid radicals which -may or may not be pure hydrocarbon substitu- III, IV and V of Mendeleefis Peri v odic Table; (f) Sulfur, selenium and tellurium compounds, such as aryl mercaptans,

aryl sulfides, aryl disulfides, arylpoly-sulfides, aryl thioestersyalkyl th'ioesters, alkyl mercaptans, alkyl monosulfides, alkyl disulfldes, alkyl polysulfides, alkali metal sulfonates and alkaline earth metal salts of sulfonic acids;

(g) Miscellaneous ring compounds comprising mercapto-benzothiazole; ox-

azines, phenthiazine, indane and acridane;

(h) Organic phosphorus compounds com-' prising oil-soluble phosphines, esters of phosphorous acids, and esters of phosphoric acid;

4. Polyvalent metal salts of acids of phosphorus containing an organic substituent, such as salts of partially esterified phosphoric acid, partially estegifled phosphorous acid, partially esterifled thio-phosphoric acids, -.and partially esterified thiophosphorous acids.

5. Polyvalent metal oxides having an alkyl or 'cyclo-alkyl group directly attached to the oxygen thereof.

Among the carboxylate esters having an albl hydroxy substituent near a carbonyl group of the compound which may be utilized in combination with each'and every one of the foregoing metal ents;' aluminum phenyl stearate, zinc phenyl stearate, tin phenyl stearate, magnesium phenyl stearate, calcium phenyl stearate, chromium phenyl stearate; aluminum naphthyl stearate, zinc naphthyl stearate, tin naphthyl stearate, magnesium naphthyl stearate, calcium naphthyl stearate, chromium naphthyl stearate; aluminum phenyl laurate, zinc phenyl laurate, tin phenyl laurate, magnesium phenyl laurate, calcium phenyl laurate, chromium phenyllaurate; aluminum alpha :benzal stearate, zinc alpha benzal stearate, tin alpha benzalstearate, magnesium alpha benzal stearate, calcium alpha benzal stearate, chromium alpha benzal stearate; aluminum alpha benzal laurate, zinc alpha benzal laurate, tin alpha benzal laurate, magnesium alpha benzal laurate, calcium alpha benzal laucarboxylates are: the methyl, ethyl, propyl, butyl,

amyl, hexyl, heptyl, octyl, nonyl; lauryl, dodecyl, tetradecyl, cetyl, and octadecyl esters of alpha or beta hydroxy propionic acid; and the corresponding esters of alpha, beta and gamma hydroxy,

rate, chromium alpha benzal laurate. Among the polyvalent metal salts of acids of phosphorus containing an organic substituent which may be utilized in combination with each and every one of the foregoing metal carboxylates are the aluminum, calcium, barium, strontium,

chromium, and magnesium salts of substituted acids of pentavalent phosphorus of the following formulae: 7

where R and R may be alkyl, aryl, alkaryl, aralkylor cyclic non-benzenoid radicals which may or may not be pure hydrocarbon constituents.

Among the polyvalent metal oxides having an alkyl or cyclo-alkyl group directly attached to the oxygen thereof which may be utilized in combination with each. and every one of the foregoing polyvalent metal alkyl carboxylates are: calcium amylate, calcium hexylate, calcium heptylate,

calcium octylate, calcium laurate, calcium dometal salts of the hereinbefore described substituted polyvelant metal alkyl carboxylates in a hydrocarbon oil of the lubricating oil class is the prevention of piston ring sticking or its marked postponement under very severe motor conditions,

as for example in Diesel engine or in aircraft spark or compression ignition engine operation. An adintervening atom to a carbon atom in the alpha position with respect to a carbonyl group of the metal carboxylate, less preferably to a carbon atom in the beta position, and of decreasing desirability and efiectiveness to carbon atoms in the gamma, delta and epsilon positions in the order named.

In the corrosion tests Whose results are summarized hereinafter, thin sheets of the indicated bearing metals were cut into strips (copper-lead, 1%" x 1%" x 5%"; cadmium-silver x 1%" x 9 and these strips were immersed in the exemplified oils carried in 2" x 20" glass test tubes, these test tubes were carried in an oil bath maintained at 300 F. (or 325 F. where indicated) :1" F. Each test tube contained approximately 300 cc. of oil, and air was bubbled through each tube at the rate of 10 liters per hour. At the end of each of three 24-hour periods, the strips were removed from the oils, washed with petroleum ether and carefully wiped with a soft cotton cloth; weight losses of the strips were measured in connection with the weight of each individual strip. The duration of the tests was 72 hours, and the weight losses tabulated below are those found at the end of the 72-hour period, except as indicated.

TABLE I Strip corrosion tests72 hours at 300 F. 10 liters of air per hour Wmght s- Inspections at 72 hours Oil Copper-le Cadmium-silver Viscosity increase Nbrlzut.

. o. 24 hours 48 hours 72 hours 24 hours 48 hours 72 hours 100 210 Acid refined naphthenic base oil S. A. E.

30+0.50% Ca cctyl succinate 26. 8 51- 8 65- 2 7 2. 6 2. 5 963 14, 2, 72 Ditto+0.fi3% Ca-cetyl (ethylthio)-sucpinate. 14.0 18.6 23. 7 4. 0 3. 9 3. 9 511. 14. 6 1. 36 Ditto-H.592, Ca cctyl alpha-mercaptosuc- Y Y cinate 8. 0 9. 8 1 0- 9 0. 8 0. 8 367 1. 60

Paraflinic base lubricating oil S. A. E. 30+

0.5% Ca cctyl alpha-mercaptosuccinate 13.2 17. 9 20. 7 2. 2 2. 2 2. 2 64 3.9 1. 01 Ditto+0.5% Ca alpha-(ethylthio)-stcarate. 50. 9 01.1 123. 3 41. 0 129. 4 203.0 216 11.0 1. 21 Acid refined naphthenic base oil S. A. E.

3()+0.5% Ca stcaratc 40. 6 103. 8 13 9 2 106. 0 180. 1, 186 27. 0 Ditt0+1% Ca (cctylthio)-acetate. 22. 0 101. 1 156. 1 10. 9 11. 1 g 10. 5 642 15.8 2. 37

I)itto+1% Ca 10-(amy1thi0)-stearat 18. 0 90. 0 164. 0 14. 5 55. 0 117. 4 988 21. 3 2. 97

1 lvhitc 011 No. 24.0 34.6 39.0 5 318 13 4.30 1 Ditt0+l% Ca stcarate 45. 3 57. 4 68- 4 4 69. 4 95. 7 548 20. 4 6. 1 Ditto+0.5% Ga alpha-(ethylthio)-stearate 12.6 29.7 49.9 15.8 23. 2 29. 7 156 6.0 2. 50 l Ditt0+1% Ca stearate+2% dicctyl sulfido. 17. 3 86. 4 140. 9 19. 0 64. 8 144. 2 115 6. 0 2. 47 l Ditto-14% Ca alpha-(ethylthio)-stearate+ 1% dicctyl sulfide 47. 5 75. 2 83- 9 12. 0 24. 4 75. 6 4. 0 3. 30

1 Nora-Tests carried out at 325 F.

ditional benefit to be derived from this invention is a decreased corrosivity toward bearing metals, particularly those of the class represented by the I cadmium-silver and copper-lead alloy types.

This diminution in corrosivity is particularly marked if the corrosivity of oils compounded with unsubstituted polyvalent metal carboxylates is compared with the corrosivity of the same oil compounded with the same amount of the corresponding polyvalent metal carboxylate having an element of Group VI-B of Mendeleeffs Periodic Table of the Elements near a carbonyl group of the carboxylate, according to the principles of this invention. This decrease in corrosivity is so extensive in some instances that the compounding agents not only are themselves non-corrosive in lubricating oils but actually may reduce the cor-' rosivity of uncompounded oils which normally become corrosive during use, e. g. highly paraflinic lubricating oils or highly refined oils such as selective solvent extracted lubricating oils. Where reduction of corrosivity is a significant factor, the sulfur atom of the substituent is preferably directly connected or connected through only one It will be observed from the above data that the substituted polyvalent metal carboxylates of this invention yield a compounded oil having greatly reduced corrosivity as compared With'the corresponding unsubstituted compounds. Attention is .also directed to the fact that substitution of the amylthio group in the .l0 position, as in calcium 10-(amylthio)-stearate, was relatively ineffective in reducing corrosivity.

A still further benefit derived from the addition of the metal carboxylates of this invention to hydrocarbon oils is a marked lessening of color instability upon the exposure of the compounded oils to heat in the absence of air or metals. In many cases, additional benefits may be derived by incorporation of the compounds of the invention in hydrocarbon oils by reason of an enhanced oiliness and/or an increased load carrying capacity of. the oils so compounded. Still further, the ability of the hydrocarbon oils to resist oxidation, i. e. absorption of oxygen when exposed thereto at superatmospheric temperatures and pressures, is in many cases enhanced andv oxygen absorption postponed by the TABLE II Oxidator results (340 F.) (cc. oxygen absorbed) Oxygen absorption Oil l min. min. min. hr.

Acid refined napbthenic base oil 8. A. E. 30 75 125 205 Ditto+0.5% Ca stearate 150 260 360 450 Ditto+0.73% Ca 10-(amylthio)- stearate 270 390 480 520 Ditto+0.25% Ca (cety1tliio)-acetats 80 125 The compounded oils of this invention have a combination of properties which is particularly desirable and difllcult to obtain. The ability to impart color stability, to inhibit oxidation, to inhibit piston ring sticking, to impart freedom from the production of increased wear, and in many instances actually to decrease wear on cylinder walls and piston rings as compared with uncompounded mineral oils and non-corrosivity as respects the chemical action of the compounded oil on bearing metals such as copperlead and cadmium silver alloys, together with the ability of certain compounds and combinations actually to decrease corrosivity of normally corrosive uncompounded oils, represents a combination of properties quite rare in single compounding agents or simple combinations thereof.

Data on the preparation of exemplary compounds and lubricants of this invention may serve to guide those skilled in the art in the practice thereof.

The-compounds may be prepared by a number of alternative methods which may involve, for example, (1) neutralization of an acid contain: ing the type of substituents herein disclosed with an alkali metal hydroxide, and addition of a water-soluble polyvalent metal salt to an aqueous dispersion of the neutralized acid whereby precipitationof the desired compound is obtained;

or (2) hydrolysis and saponification of the neutral ester to form an alkali metal salt of the acid of the ester, and precipitation of the polyvalent metal salt from the saponifled product. Where polycarboxylic acids are utilized as the saltforming agent an acid ester may first be formed or the neutral ester partially hydrolyzed and saponifled to obtain compounds from which the polyvalent metal carboxylates of this invention may be formed. In some instances it is feasible to introduce the substituents disclosed herein into a salt of an unsubstituted acid and thereby produce a substituted carboxylate of the type utilized in this invention.

Preparation of alpha (ethylthio) -stearic acid.13.3 grams of NaOHwas dissolved in 25 cc. of H20 and diluted to 500 cc. with alcohol. 27 cc. of ethyl mercaptan was added and the solution heated to boiling. 20 grams 0! NazCOa (6 dissolved in 300 cc. of H20 was added to 113 grams of alpha-bromostearic acid dissolved in was dried in a vacuum desiccator. Yield-404 gr.

% sulfur8.53.

Preparation of calicum alpha (ethylthio)- stearate and concentrate thereof.25 grams of the crude acid was added to H20 and heated with steam. 50% KOH was added until the solution was just basic to phenolphthalein and 10% 09.012 solution added until the precipitate firstformed coagulated. 25 gr. of a heavy white-oil was added and the material steamed. The water was then decanted on and the oil concentrate brightened by heating to 320 F. and filtering with the aid of super-eel. Percent calcium in concentratel.88%. This concentrate was utilized for compounding finished lubricating oils by addition of a suitable amount of the concentrate to give the desired proportion of the calcium alpha (ethylthio)-stearate in the finished oil.

Preparation of calcium (cetylthio)-acetate.- 64.5 gms. of cetyl mercaptan were dissolved in warm ethyl alcohol containing 17 gms., of sodium ethylate and the resulting solution was poured into a fiask equipped with a stirrer, condenser and dropping funnel. To the material in the flask was added an alcoholic solution of sodium chloroacetate prepared by neutralizing 23.62 gms. of chloroacetic acid with 21 gms. of sodium bicarbonate in a small amount of water and adding alcohol, After the additon of the sodium chloroacetate the reaction mixture was heated and stirred for 45 minutes, which effected solu tion of the precipitated sodium (cetylthio)-acetate. The hot alcohol solution was filtered to free it from sodium chloride. The hot filtrate was treated with 13.9 gms. of calcium chloride in aqueous solution. The precipitated calcium (cetylthio)-acetate was washed free of chloride ion and dried. The yield was 70 gms. (84% of theoretical). The following analytical data were obtained:

Per cent Sulfur 7.64 Calcium 4.75 Chlorine 0 Ash 8.00

Preparation of calcium cetyl alpha-mercaptosuccinate.47 gms. of powdered calcium cetyl fumarate were warmed with gms. of hydrogen sulfide in a steel bomb for 27 hours, the pressure reaching a maximum of 300 lbs. per square inch. 49 gms. of hydrogen sulfide-free product were obtained (theoretical yield-52.5 gms.). The analytical data obtained were as follows:

Per cent Sulfur 2.02

Ash 7.85

to drive off excess mercaptan, The salt was then washed with ethyl alcohol and dried. Yield 66 gms. (56% of theoretical). The following analytical data were obtained:

Per cent Sulfur 4.19 Calcium 6.45 Ash 11.37

Preparation of compounded oils.In general,

the compounding agents of this invention are to sufficient mineral lubricating oil to dilute to' throughout this specification in percent by weight based on the oil, unless otherwise indicated.

In general, the polyvalent metalalkyl carboxylates of this invention preferably contain at least about ten carbon atoms. Where the organic alkyl hydroxy pure esters are utilized in combination with the'metal carboxylates and reduced corrosion is desired, the ester-should preferthe desired final concentration. In some cases,

, it is necessary to heat the final oil so compounded to a fairly high temperature for a suflicient time to destroy a false viscosity or thickening of the oil which results if a lower temperature is employed. For compounds of low solubility, it is also necessary to aid solution by stirring at relatively high temperatures and for longer periods of time.- The oil is finally filtered through a filter press, preceded by centrifuging where necessary.

The proportion of'the polyvalent metal alkyl carboxylates of this invention which is added to mineral lubricating oils may vary widely depending upon the. uses involved and the proper-, ties desired. As little as 0.1% by weight of the polyvalent metal alkyl carboxylates gives measurable improvements, although from approximately 0.25% to approximately 2% is preferred where the compounded oil is to be used as a crankcase lubricant for internal combustion engines. Similarly, the proportion of the carboxylate esters having an alkyl hydroxy substituent near a. carbonyl group of the ester may vary widely but in general from 0.1% to 5% of the 'ester is utilized in combination with the polyvalent metal alkyl carboxylates, and more usually 0.5% to 2% thereof is found desirable. More than 10% is regarded as unnecessary, except when a concentrate is being prepared for subsequent dilution with mineral oil to produce .the finished lubricant. The proportion of metal salts of other organic acids, such as the aliphatic acids,'naphthenic acids, phenolic acids, and aryl carboxylic, likewise may vary from 0.1% to 5% and, more usually, from 0.5% to 2% when utilized in combination with polyvalent metal alkyl carboxylates. The corrosion inhibitors and antioxidants represented by the various types listed on pages and 26 may be present with the polyvalent metal alkyl carboxylates in an amount of from about 0.05% to 2%, or more, The polyvalent metal salts of acids of phosphorus containing anorganic substituent when utilized in combination with the polyvalent metal alkyl'carboxylates may be added in amounts from 0.05% to about 2%, or more. 'Usually 1% or less is found adequate. The polyvalent metal oxides having an alkyl or cycloalkyl group attached to the oxygen thereof may be added in amounts of from 0.05%, or less, to 5% and preferably 0.1% to 2% whenused in combination with the polyvalent metal alkyl carboxylates. In each of the above instances the proportions of ingredients may be very materially increased when a concentrate is being prepared for subsequent dilution with lubricating oil. Proportions are given ably contain less than ten carbon atoms. Where reduced friction at low rubbing speeds is a paramount factor, more than ten carbon atoms in the, ester are preferred. Cooperation with polyvalent metal alkyl carboxylates to yield increased stability against oxidation may be obtained where the esters contain either ten or less carbon atoms, or more than ten carbon atoms. However, more than '75 carbon atoms in the ester are regarded as unnecessary.

The concentrates previously referred to may be prepared and distributed as a hydrocarbon oil or other organic solution containing relatively large portions of the additive agents. The solvent may be hydrocarbon oils of the lubricating or less viscous type or, if more suitable, an admixture with oil of certain other agents, such as aromatic hydrocarbons, alcohols, esters, ketones or ethers, which are generally of low molecular weight and of the aliphatic series. These latter blending agents may serve to improve the solubility relationships or the like of the compounds. Admixtures .of the addition agents and. lubricating oils or other solvents or carriers containing 50% or more of the essential agents by weight may be thus prepared and distributed for later blending with the particular lubricating oil media to be put to use as occasion demands. In the preparation of either the finished oils of the invention or of the bases or concentrates referred to, complete or clear and homogeneous solution is not always necessary. Stabilizing or blending agents may be employed to prevent sedimentation of the more oil-insoluble addition agents. The possible detrimental effect of the presence of filterable insoluble materials of this character, if they be present, is determined largely by the particular conditions attending the contemplated use and their presence is not in all cases deleterious to the functioning of the composition in its intended manner.

The compounded lubricant herein disclosed .may have one or more advantages depending upon the particular compounds selected, the proportions utilized, and the environment which the lubricating oil is to encounter. It should be observed, for example, that even though a compounded oil may not be entirely non-corrosive to copper-lead or cadmium-silver alloys, other bearing metals may be little if at all affected by such corrosive action. Hence, com-pounding agents or combinations thereof which may not be particularly desirable for one service, where corrosion at high temperatures becomes a factor of importance, may nevertheless .be highly useful and extremely advantageous in other services. Likewise, a compounding agent which may not be suficiently powerful to adequately stabilize a particular oil stock against deterioration under the most severe conditions may be highly ad- The present invention in its broader aspects is therefore not limited to the particular compounding ingredients having the greatest stability or having all of the advantages of the preferred agents or combinations of agents. The invention embraces various of the less advantageous compounding agents or combinations thereof which may find utility in particular applications where all possible improvements in properties of the oil may not be required or where the standard of performance may not be so high.

The term "carbonyl group is used throughout the specification and claims to include esterified or neutralized carboxyl groups, i. e. the roup where X may be either a metal or an organic radical.

The compounding ingredients of this invention are not limited in their applicability to any particular base oil stock. The advantages herein disclosed may be obtained with various oil stocks, the selection of which will be determined by conditions and services which the compounded lubricant is to encounter. The compounding ingredients are useful not only in Pennsylvania oils or highly refined naphthenic base oils, but also in moderately refined naphthenic base oils or in lubricating oils from Mid-Continent stocks, as well as in synthetic hydrocarbon oils, such as hydrogenated polymers of olefin hydrocarbons or condensation products of chlorinated alkyl hydrocarbons with aryl compounds.

The compounding ingredients of this invention may be utilized in hydrocarbon oils containing other compounding agents, such as pour point depressants, extreme pressure addition agents, blooming agents and the like. Also, the compounds are useful in greases, e. g. a grease comprising a mineral oil and a sodium soap.

The term Group VIB of Mendeleeffs Periodic Table of the Elements as used in the specification designates the elements listed on the righthand side of Group VI in the Periodic Arrangement of the Elements given, for example, in Langs Handbook of Chemistry, 1934 edition.

Our copending application Serial No. 322,946, filed March 8, 1940, is directed to those aspects of the present disclosure pertaining to salts of polycarboxylic acids.

While the character of the invention has been described in detail and numerous examples given, this has been done by way of illustration only and with the intention that no limitation should be imposed upon the-invention thereby. Numerous modifications and'illustrations of the illustrative examples may be effected in the practice of the invention which is of the scope of the claims appended hereto.

We claim:

1. A composition comprising a hydrocarbon lubricating oil and a metal salt of an alkyl carboxylic acid characterized by the presence of the group R- X -B-Y, where R is selected from the group consisting of hydrogen and radicals of alkyl structure, X is a substituent with at least one atom of an element of Group VIB of Mendeleefis Periodic Table of the Elements, B is an alkyl group of no more than three carbon atoms, and Y is selected from the group consisting of m 2. A composition comprising a hydrocarbon lubricating oil and a metal salt of an alkyl carboxylic acid characterized by the presence of the group R-XBY, where R is selected from the group consisting of hydrogen and radicals of alkyl structure, X is a homoatomic substituent with at least one atom of an element of Group VIB of Mendeleefis Periodic Table of the Elements, B is an alkyl group of no more than three carbon atoms, and Y is selected from the group consisting r of COH, o-0n, c-sn, and c-sn 3. A composition comprising a hydrocarbon lubricating oil and a metal salt of an alkyl carboxylic acid characterized 'by the presence of the group R-X-B-Y, where R is selected from the group consisting of hydrogen and radicals of alkyl structure, X is a heteroatomic substituent with at least one atom of an element of Group VI--B of Mendeleefi's Periodic Table of the Elements, B is an alkyl group of no more than three carbon atoms, and Y is selected from the group consisting of- 4. A composition comprising a major proportion of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl monocarboxylate containing at least ten carbon atoms and having at least one atom of an element of Group VIB of Mendeleeff's Periodic Table of the elements attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of said oil and said element of Group VI-B mitigating the catalytic action of the metal atom of the carboxylate.

5. A composition comprising a major proportion of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl monocarboxylate containing at least ten carbon atoms and having a homoatomic substituent with at least one atom of an element of Group VIB of Mendeleefis Periodic Table of the Elements attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of. said oil and said element of Group VIB mitigating the catalytic action of the metal atom of the carboxylate.

6. A composition comprising a major proportion'of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl carboxylate containing at least ten carbon atoms and having a heteroatomic substituent with at' least one atom of an element of Group VIB of Mendeleeffs Periodic Table of the Elements attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate,-said carboxylate inhibiting said deterioration of said oil and said element of Group VIB mitigating the catalytic action of the metal atom of the carboxylate.

7. A composition comprising a major proportion of a hydrocarbon lubricatingoil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl monocarboxylate containing at least ten carbon atoms and having at least one atom of sulfur attached to an aliphatic ate, said carboxylate inhibiting said deterioration of said oil and said sulfur mitigating the catalytic action of the metal atom of the carboxylate. v

8. A composition comprising a major proportion of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl carboxylate containing at least ten carbon atoms and having at least one atom of selenium attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of said oil and said selenium mitigating the catalytic action of the metal atom of the carboxylate.

9. A composition comprising a major proportion of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by weight of a metal alkyl carboxylate containing at least ten carbon atoms and having at least one atom of tellurium attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of said oil and said tellurium mitigating the catalytic action of the metal atom of the carboxylate.-

10. A composition comprising a major propor-' tion of a hydrocarbon lubricating oil subject to deterioration and from about 0.1% to 2.0% by 0 weight of a metal alkyl carboxylate containing at least ten carbon atoms and having atleast one atom of an element of Group VIB of Mendeleeff s Periodic Table of the Elements attached to an aliphatic'carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of saidoil and said element of Group VI-B mitigating the catalyticone atom of an element of Group VI-B of Mendeleefis Periodic Table of the Elements attached to an aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of said oil and said element of Group VI-B mitigating the catalytic action of the metal atom of the carboxylate; and from about 0.05% to 2.0% by weight of an alkylthio ether.

12. A composition comprising a major proportion of a hydrocarbon lubricating 'oil subject to-' deterioration and from about 0.1% to 2.0% by weight of a metal alkyl carboxylate containing at least ten carbon atoms and having at least one atom of an element of Group VI-B of Mendeleefis Periodic Table of the Elements attached toan aliphatic carbon atom not more than three carbon atoms removed from a carbonyl group of the carboxylate, said carboxylate inhibiting said deterioration of said oil and said element of Group VI-B mitigating the catalytic action of the metal atom of the carboxylate; and

from about 0.05% to 2.0% by weight of a poly- Y 14. A lubricating composition comprising a major proportion of a hydrocarbon lubricating oil'subject to deterioration and a small amount suflicient to inhibit said deterioration of an alkaline earth metal mercapto alkyl monocarboxylate containing at least ten carbon atoms, said mercapto group being no more than about three carbon atoms from a carbonyl group of said carboxylate to inhibit the catalytic action of said alkaline earth metal.

15. A lubricating composition comprising a major proportion of a hydrocarbon lubricating oil subject to deterioration and, a small amount suflicient to inhibit said deterioration of an alkaline earth metal thioketo alkyl carboxylate containing at least ten carbon atoms, said thioketo group being no more than about three carbon atoms from a carbonyl group of said carboxylate to inhibit the catalytic action of said alkaline earth metal. v

BRUCE B. FARRINGTON. JAMES O. CLAYTON. I 'DORR H. ETZLER. 

